This Phase II randomized, double-blind placebo-controlled study is being done to determine the effects of subcutaneous r-metHuLeptin on glycemic control in obese subjects with diet-treated non-insulin dependent diabetics. Secondary objectives are to assess changes in body weight, body composition, waist circumference, and fasting levels of plasma insulin and lipids. The safety and tolerability of r-metHuLeptin will also be assessed.